The present invention relates to cutting blade assemblies and, more specifically, to cutting blade assemblies for rotary weed trimmers.
Individuals and commercial enterprises have made weed trimmers very popular due to the ease of use, speed and fine trimming capabilities of these devices. Rotary weed trimmers utilizing plastic "string" cutting heads have been especially popular. While the "string" cutters are effective on grass and some weeds, they are not effective for cutting heavy weeds, vines, brush and other heavy undergrowth. The requirement for flexibility significantly limits the durability of the string, requiring frequent replacement. Although cutting heads for "string" cutters utilize reels of string to provide replacement string material, feeding is often cumbersome and imprecise. Cutter heads offering string feed mechanisms are often complicated and resulting seams and mechanisms in the head result in increased opportunity for breakage and entanglement with weeds, vines and foreign materials
Trimmer blades with fixed or pivoting blades offer improved performance in cutting heavier vines and undergrowth. However, cutter heads for these blades are often complicated or employ exposed blade pivots resulting in entanglement of the cutter assembly. Blades are often plastic and short in comparison with the diameter of the cutter head. Trimmers employing these type of cutter heads suffer from missed areas when the trimmer blade assembly is moved rapidly. Reliability and durability of the blade assemblies is poor in heavy cutting environments.